贵州省烂泥沟金矿大角度斜直深孔绳索取心钻探技术

Rope Coring Dilling Technique of Large Angle Inclined Straight Deep Hole in Lannigou Gold Mine, Guizhou Province

矿产资源勘查随着程度的提高和深度的增加,对于钻孔防斜保直要求越来越高。贵州省烂泥沟金矿2021年度勘查设计7个超过千米的大角度斜直孔(顶角20°~32°之间),要求每百米顶角和方位角偏斜均不超过1°,绳索取心工艺仅靠传统方式难以保证该精度。项目实施过程中,钻探施工单位采用光面扶正器和液动冲击钻进方式进行防斜保直;采用调整钻具组合、短距反复切削、换径重复导向扩孔方式进行升降顶角;采用正反交替钻进方式进行纠方位。通过上述措施有效地达到了预期目标,所形成的经验对于类似大角度斜直深孔取心钻探具有一定借鉴价值。

With the development of mineral resources exploration and the increase of mineral buried depth, the requirements for borehole deviation prevention and straightness maintenance are increasing.In 2021,it designed 7 high deviation angle deep straight holes with a depth of more than 1,000 meters(deviation angle were between 20° and 32°)in the exploration of Lannigou gold mine in Guizhou province.Each hole required that the deviation angle and azimuth angle should not exceed 1° per 100 meters.However, the rope coring technology could not guarantee such accuracy only by traditional methods.During the implementation of the project, the drilling construction side used smooth centralizers and hydraulic impact drilling methods to prevent deflection and keep straight.The top angle is lifted and lowered by adjusting the drilling tool assembly, repeated cutting at short distances, and repeated guiding and reaming when changing diameters;Alternate forward and reverse drilling methods are used to correct orientation.Through the above measures, the expected goal has been effectively achieved, and the experience formed has certain reference value for coring drilling of similar large-angle oblique straight deep holes.